Image source, Reuters

We've been reporting for days now about the desperate situation in the southern port city of Mariupol, where 100,000 people remain trapped without food, water or power and enduring fierce shelling by Russian forces.

Many people have been hiding in basements and Ukraine's President Volodymyr Zelensky said earlier this week that there was "nothing left" of the city.

Efforts to establish humanitarian corridors to allow civilians to leave and for aid to be delivered have repeatedly failed.

Mariupol has become the most heavily bombed and damaged city in Ukraine's war with Russia. It's key to Moscow's military campaign in Ukraine.

Geographically, the city occupies only a tiny area on the map, but it now stands obstinately in the way of Russian forces who have burst out of the Crimean peninsula.

They are pushing north-east to try to link up with their comrades and Ukrainian-separatist allies in the Donbas region of eastern Ukraine.

But Ukrainian forces have been holding firm.

Read more on why Mariupol is so important to Russia's plan.

Yana is 10 years old and has fled the war in Ukraine.

She started school in the Polish capital Warsaw just three weeks ago and has already made a new best friend, Alicja.

There are already 60 Ukrainian refugee students in the school, and many more are expected to arrive.

Yana is just one of more than three million refugees who have fled Ukraine since the Russian invasion began a months ago.

Poland has borne the bulk of these migrants, welcoming nearly two million of them - half of whom are children.

Image source, Getty Images

Ukraine's President Zelensky has used his latest nightly video address to make an impassioned plea for people to take to the streets to demand an end to the war.

As our diplomatic correspondent Paul Adams reports, it's the latest example of how, away from the battlefields, Zelensky has been waging an information war on the capitals of the Western world.

He's addressed 10 parliaments in two weeks, receiving standing ovations everywhere.

Live by video link from a besieged capital, wearing a green t-shirt and sporting several days of stubble, he often signs off with a clenched fist salute. As applause rings out, he disappears. He's a man in a hurry, after all, with truly existential matters to attend to.

"He knows how to embody the spirit of the nation," says Jonathan Eyal, of the Royal United Services Institute. "Not only in speech, but also in the way he appears, in his backdrop, where he speaks."

Read more from Paul on how Zelensky is using his highly tailored speeches to muster international support.

Jessica Parker in Brussels & Jonathan Beale in Norway

Image source, Getty Images

US President Joe Biden joins fellow Western leaders in Brussels on Thursday for three summits on Russia's war in Ukraine, a month after the invasion began.

One issue that will inevitably come up for discussion is the level of Europe's willingness to engage militarily in the conflict.

Nato leaders have already sent thousands more troops to the alliance's eastern flank, along with more air defence batteries, warships and aircraft in a bid to boost its own defences.

But not all have been willing to supply weapons.

The alliance has also made clear it won't become more directly involved and Mr Zelensky's repeated requests for a no-fly zone over Ukraine has been ruled out.

Nato has also yet to decide how it would respond if Russia were to dramatically escalate the conflict in Ukraine - such as an attack on a Western weapons convoy, and the use of chemical, or even tactical nuclear weapons.

Read more about what's at stake as Western leaders meet.

In the month since Russia's military invaded Ukraine, it has laid waste to cities across the country.

This drone footage shows the extent of devastation in Kyiv, Mariupol and other places across the war-torn country.

Image source, Ukraine Presidency

Ukraine's President Zelensky made an impassioned plea for people all over the world to take to the streets on Thursday to show their support for Ukraine.

He gave his latest nightly video address earlier - and it was in English for the first time.

Russia's war was not just against Ukraine, he said, but the freedom of people everywhere - and the world needed to stop Russia's crude use of force.

"Come from your offices, your homes, your schools and universities, come in the name of peace, come with Ukrainian symbols to support Ukraine, to support freedom, to support life," the president said.

Zelensky's address came hours before a Nato summit in Brussels where Western countries are expected to agree on sending reinforcements to Central and Eastern Europe to bolster the bloc's defences.

US President Joe Biden will be attending the meeting on a day that will mark one month since the Russian invasion began.

Asian shares fell on Thursday as traders and investors reacted to the latest developments in the Ukraine war, which has been underway for a month now.

Morgan Stanley Capital International's Asia-Pacific index of equities dropped 0.6%.

Japan's Nikkei 225 index fell by more than 1% on Thursday morning, after touching a two-month high in the previous session. China's markets also opened lower on Thursday morning.

This comes as US President Joe Biden arrived in Brussels, and is expected to announce a new set of sanctions on Russian oligarchs and political figures.

Oil prices remained level. Brent crude - the international benchmark for oil prices - rose by 45 cents or 0.4%, at $122.05 a barrel.

Russia is moving troops to Ukraine's borders after suffering heavy losses during the war, Ukraine's military claims.

In its latest update on the conflict, the General Staff of the Armed Forces of Ukraine says that "due to suffering numerous losses" Russian forces "continue to form and move additional units of armed forces of the Russian Federation to the Ukrainian borders".

It claims "contracting measures have been intensified" by military officials in Russia's western Smolensk region.

"Servicemen returning after a business trip from Syria are also being recruited to replenish the occupation units," it says.

The BBC is unable to independently verify this information.

As we reported earlier, Nato officials believe some 7,000 to 15,000 Russian troops may have been killed in the first month of the conflict, with the number of wounded perhaps between 30,000 and 40,000.

Anthony Zurcher
BBC North America correspondent

Image source, Getty Images

US president Joe Biden will meet European leaders and allies on Thursday - in the backdrop of an international crisis with no end in sight.

What are some of the biggest challenges he will face on this trip?

1. A show of unity

The US has so far moved in step with its allies, especially in the early days of the war when urgency removed some traditional obstacles to consensus.

But as the war drags on, the potential for discord will increase. Biden will have to convince his allies that strengthened Nato resolve is not a temporary condition but the new normal.

2. Refugee crisis

Poland has borne the bulk of Ukrainian refugees fleeing the Russian invasion. Throwing its borders open to millions of refugees has put considerable strain on the country and, if not handled competently, could lead to social unrest and economic instability.

Ensuring the nation remains a reliable Nato member is a pressing US concern.

3. Military solutions

While the US has promised to provide more advanced long-range air defense capabilities to Ukraine, it is easier said than done.

There are concerns over the kinds of anti-air support that would ignite a Russian response against Nato and the logistics of getting weapons into Ukrainian hands - none of which can be accomplished without the US' European allies.

4. A sanctions roadmap

Crushing international sanctions - led by US and Europe - have done little to deter Russia from continuing its full-fledged assault on Ukraine.

While western allies insist the pain of sanctions will increase over time, there is growing pressure on US and European leaders to find new ways of punishing Russian aggression.

5. The China question

Both America and Europe will need to make co-ordinated efforts to convince China to keep its distance from Russia and, if possible, be more vocal in its condemnation. The threat of sanctions on China if it were to openly aid Russia is already weighing on the Chinese economy.

But China's recent backing of Russian participation in the upcoming G20 economic summit suggests the task will not be easy.

Image source, Getty Images

Russia has said it will expel a number of US diplomats in a tit-for-tat move after the US' decision to remove 12 Russian diplomats.

Washington last month said it was expelling the Russian diplomats at the country's UN mission in New York over national security concerns, and later announced it would oust an additional Russian at the UN who it claimed was a spy.

On Monday, the Russian foreign ministry summoned US Ambassador to Russia John Sullivan to protest President Joe Biden’s labelling of Russian leader Vladimir Putin as a “war criminal”.

A State Department spokesperson later confirmed they had "received a list of diplomats declared 'persona non grata' from the Russian Ministry of Foreign Affairs on March 23."

Persona non grata is a term used to indicate that a person is no longer welcome or accepted.

It is not clear how many US diplomats will be affected by the order, and when they will be expelled from Russia.

Image source, Reuters

If you're just joining us, here's the latest:

• Russian troops are growing increasingly demoralised, according to Western intelligence agencies, and risk becoming encircled in the Kyiv suburbs
• Almost all of Irpin, which has seen fierce fighting in recent weeks, is back in Ukrainian hands, says Kyiv's mayor

• Russian forces are continuing to bombard and blockade the southern port city of Mariupol, where residents have run out of water and food and an estimated 90% of the city's buildings have been damaged or destroyed
• Bombs continue to fall in cities around the country, including Kyiv, Chernihiv and Kharkiv

• After speaking to Ukrainian President Volodymyr Zelensky on Wednesday, UK PM Boris Johnson will pledge on Thursday to give Ukraine 6,000 missiles
• Earlier, Sweden announced that it was providing 5,000 anti-tank missiles to Ukraine
• Putin told ministers that gas sales to "unfriendly" nations will go forward in roubles, unsettling the energy markets

• Tributes have poured in for Oksana Baulina, a Russian opposition activist and journalist who was killed by Russian fire in Kyiv

This is Jude Sheerin and Max Matza signing off in Washington DC and handing over to our colleagues, Aparna Alluri in New Delhi and Zubaidah Abdul Jalil in Singapore.

Image source, Ukrainian government

In his nightly video address, Ukraine President Volodymr Zelensky warned western leaders meeting in Brussels that Russia is exerting its economic might to stop Ukraine's allies from intervening in the war.

"We know that the Russians have already begun to lobby their interests. These are the interests of war. We know that they are working with some partners," Zelensky said ahead of the G7, Nato and European Union summits being held in Brussels on Thursday.

"Our firm position will be represented at these three summits," he continued.

"At these three summits we will see: Who is a friend, who is a partner, and who betrayed us for money."

Around 40% of Europe is powered by Russian gas. European leaders have been seeking alternate sources of energy as they lob sanctions on Moscow.

Zelensky will address the Nato summit via video-link, and is expected to call for more advanced weaponry, including plane and anti-aircraft systems.

Image source, Getty Images

Between 7,000 and 15,000 Russian troops have died after one month in the invasion of Ukraine, a senior Nato official told AP News on Wednesday.

The official added that 30,000 to 40,000 Russians are thought to have been killed or wounded in the fighting.

Russia has not provided an official death toll since 2 March, when it said that 500 of its troops had died.

For context, Russia lost about 15,000 troops in its 10-year occupation of Afghanistan.

Ukraine has also been vague about its own dead, with Ukraine's president saying about two weeks ago that 1,300 Ukrainian troops had died.

Intelligence will supplement weapons boostpublished at 02:33 Greenwich Mean Time 24 March 2022

02:33 GMT 24 March 2022

James Landale
Diplomatic correspondent

Britain has already given Ukraine 4,000 anti-tank weapons. These portable bazookas – fired from the shoulder - have proven highly effective.

Now, among the latest promised tranche of weapons the UK will send, a further 3,000 of these will be going to Ukraine, along with a similar number of what Downing Street described as “high explosive missiles”.

These could include anti-aircraft weapons. But crucially, No 10 said the UK would also now help Ukraine with intelligence and longer range targeting.

That suggests - potentially - other uses for the missiles.

Boris Johnson will set out the details at Thursday’s Nato summit where he will urge other leaders to provide more military support for Ukraine.

Western officials say Ukrainian forces are facing shortages of weapons and that could get worse if the conflict settles into a bloody war of attrition. Besides weapons, the UK will also give Ukraine £25m to help pay the salaries of its armed forces.

Image source, EPA

A team of US national security advisers has been quietly holding mock drills to workshop different potential responses if Russia should use chemical, biological or nuclear weapons, according to the New York Times, external.

The group is also holding classified sessions to determine a response in case Moscow expands its war into other neighbouring territories, the NY Times reports.

And they are discussing ways to help European allies as they struggle to accept the millions of refugees leaving Ukraine.

The so-called White House "tiger team" was formed in October, according to the Washington Post.

The heavily bombed port city of Mariupol has been under sustained Russian attack.

The city stands in the way of Russian forces who are trying to make their way north-east from Crimea and link up with Russian troops and allies in eastern Ukraine.

Around 100,000 people are still trapped in the port city, without food, water or heat.

An official who recently fled Mariupol has told the BBC that while much of the city is destroyed, the port area is largely intact.

That's borne out by satellite images of the port, taken on Wednesday morning, which show no obvious signs of damage:

Image source, Maxar

Image source, Maxar

Image source, Maxar

Read more from our security correspondent Frank Gardner on why capturing Mariupol is so important to Russia's war effort here.

More now on the death of journalist Oksana Baulina, who's been killed by Russian fire in Kyiv.

A former magazine journalist turned opposition activist, she had to leave Russia after working for several years with the now jailed anti-corruption campaigner Alexei Navalny on his YouTube channel.

Fellow Russian journalist Alexey Kovalyov - who recently fled Russia himself -described , externalBaulina as someone with a "phenomenal sense of moral clarity".

US journalist Lucian Kim also paid tribute to her.

You can read about Baulina more here

Image source, Getty Images

Ukraine is using facial recognition software to identify the bodies of dead Russian soldiers and inform their families, Ukraine's vice-prime minister told Reuters on Wednesday.

Mykhailo Fedorov, who also runs Ukraine's ministry of digital transformation, said the country is using technology provided by New York-based company Clearview AI.

According to Clearview's founder, the company has access to more than two billion images from the Russian social media service VKontakte.

The service is being provided for free to Ukraine, and is not being provided to Russia, Reuters reported.

Ukraine has set up an online form for Russians seeking to claim the bodies of their dead. Ukraine claims that over 14,000 Russian troops have died, but those numbers have not been verified.

Officials in Ukraine say Russia has destroyed a key bridge over the Desna river, cutting off a vital route between the northern city of Chernihiv and the capital Kyiv.

Ukraine's ombudsman for human rights, Lyudmyla Denisov, said the bridge had been used to bring humanitarian aid to the city and evacuate civilians.

"The city has no electricity, water, heat and practically no gas, and the infrastructure has been destroyed," she said.

The head of the regional administration, Viacheslav Chaus, said in a video statement that aid would still be delivered, and a new bridge would be built "after our victory".

Image source, Ukraine Emergency Services

Here are some photos from Ukraine on Wednesday 23 March.

Image source, Getty Images

Image source, Getty Images

Image source, Getty Images

Image source, Getty Images

Image source, Getty Images